Balloon catheter

A balloon catheter comprising:

• a shaft extending from a proximal side toward a distal side in a longitudinal direction;
• and
• a plurality of balloons disposed at a distal portion of the shaft,
• wherein, in a cross-section at a distal end of the shaft and perpendicular to the longitudinal direction, the shaft has an inner lumen and a lumen group constituted by a plurality of outer lumens disposed on an outer side with respect to the inner lumen and aligned in a circumferential direction of the inner lumen,
• wherein, in a cross-section at a distal end of the shaft and perpendicular to the longitudinal direction, the lumen group includes a first outer lumen, a second outer lumen disposed adjacent to the first outer lumen in the circumferential direction of the inner lumen, and a third outer lumen disposed adjacent to the first outer lumen and on a side opposite to the second outer lumen in the circumferential direction of the inner lumen, and
• wherein, in a cross-section perpendicular to the longitudinal direction, the shaft includes a portion in which a distance between a center of the first outer lumen and a center of the second outer lumen is larger than a distance between a center of the first outer lumen and a center of the third outer lumen.